微波无线传能系统中直流阻抗匹配器设计

Design of Direct-circuit Impedance Matcher in microwave Wireless Energy Transfer System

微波无线传能系统存在整流电路输出直流功率随直流负载变化而急剧下降,以及多路不同功率直流合成效率低的问题。为解决上述问题,本文探索在整流电路和直流负载之间设计直流阻抗匹配器。通过场效应管控制阻抗匹配器的开断实现输入电压与平均输入电流之比不变,从而保证匹配器的等效输入阻抗恒定不变,达到与整流电路匹配的目的。设计和制作了一款输入阻抗为400欧姆的直流阻抗匹配器。测试表明,即使直流负载从400~6000欧姆大动态变化,该直流阻抗匹配器能够稳定地实现约60%整流效率。对两路直流功率合成,与直接合成相比,该直流阻抗匹配器将合成效率提升了5.75%~19.18%。

In the microwave wireless energy transmission system,there are two problems that the direct-current(DC)power outputted by the rectifier circuit drops sharply with the change of the DC load,and the DC synthesis efficiency of multiple powers is low.In order to solve the above problems,this paper explores the design of a DC impedance matcher between the rectifier circuit and the DC load.The ratio of the input voltage to the average input current is kept constant by the breaking of the FET control circuit,thereby ensuring that the equivalent input impedance of the circuit is constant and matching the rectifier circuit..A DC impedance matching device with an input impedance of 400 ohms is designed and fabricated.Tests show that even if the DC load changes dynamically from 400 to 6000 ohms,the DC impedance matcher can stably achieve about 60%rectification efficiency;for the two-way DC power synthesis,in comparison with the direct synthesis,the DC impedance matcher increases the synthesis efficiency by 5.75%~19.18%.